structured.py — langchain Source File

Source Code

"""Structured prompt template for a language model."""

from collections.abc import AsyncIterator, Callable, Iterator, Mapping, Sequence
from typing import (
    Any,
)

from pydantic import BaseModel, Field
from typing_extensions import override

from langchain_core._api.beta_decorator import beta
from langchain_core.language_models.base import BaseLanguageModel
from langchain_core.prompts.chat import (
    ChatPromptTemplate,
    MessageLikeRepresentation,
)
from langchain_core.prompts.string import PromptTemplateFormat
from langchain_core.runnables.base import (
    Other,
    Runnable,
    RunnableSequence,
    RunnableSerializable,
)
from langchain_core.utils import get_pydantic_field_names


@beta()
class StructuredPrompt(ChatPromptTemplate):
    """Structured prompt template for a language model."""

    schema_: dict | type
    """Schema for the structured prompt."""

    structured_output_kwargs: dict[str, Any] = Field(default_factory=dict)

    def __init__(
        self,
        messages: Sequence[MessageLikeRepresentation],
        schema_: dict | type[BaseModel] | None = None,
        *,
        structured_output_kwargs: dict[str, Any] | None = None,
        template_format: PromptTemplateFormat = "f-string",
        **kwargs: Any,
    ) -> None:
        """Create a structured prompt template.

        Args:
            messages: Sequence of messages.
            schema_: Schema for the structured prompt.
            structured_output_kwargs: Additional kwargs for structured output.
            template_format: Template format for the prompt.

        Raises:
            ValueError: If schema is not provided.
        """
        schema_ = schema_ or kwargs.pop("schema", None)
        if not schema_:
            err_msg = (
                "Must pass in a non-empty structured output schema. Received: "
                f"{schema_}"
// ... (124 more lines)